Helhetlig helse- og miljørisikovurdering av eksplosivforurensninger i Demoleringsfeltet i Svånådalen, Hjerkinn

Very high concentrations of explosives in soils have previously been found at the demolition field in Svånådalen at Hjerkinn shooting range. A risk assessment of this “worst case” area has been conducted with regard to humans, grazing animals and birds in order to indicate the risk associated with similar contaminated areas in Norway. Representative soil and water samples were collected using a multi increment sampling strategy from different locations at the demolition field. High concentrations of TNT (mean concentration: 1058 mg/kg) and RDX (mean concentration: 107 mg/kg) was found in the soil. HMX and 2-and 4-ADNT was also found, but in lower concentrations. 2-ADNT and 4-ADNT are decomposition products of TNT. A large amount of visible TNT particles was found on the soil surface, and these particles were estimated to represent one ton of TNT for the entire demolition field. In water moderately to high concentrations of TNT, RDX, HMX, and 2 - and 4-ADNT were found. The risk assessment showed that: • The demolition field is unsuitable for small children, since they are likely to ingest particles of TNT and become acutely poisoned. • For adults, it was found that the risk was acceptable. • It is recommended that body-covering clothing and gloves are used during work in such fields. Work that generates dust, such as excavation, should be carried out with respiratory protection. • There was no significant risk to sheep in the demolition field. This is mostly due to the limited exposure time for the sheep in the field. Another important finding was that the probability for sheep to ingest particles of explosives from the ground was low. • The risk was also acceptable for the grouse. • RDX have higher acute toxicity than TNT and can be a problem for grazing animals and birds in places where RDX dominate as surface contamination.